Omega-3s May Help Lower Breast Cancer Risk, Says Study

Philadelphia, PA—Statistics show that about 200,000 women are diagnosed with breast cancer each year. A woman’s genetic makeup along with long-term exposure to estrogen are believed to elevate her risk for the disease. However, Jose Russo and his team at Fox Chase Cancer Center, based here, believe omega-3 fatty acids may lessen estrogen’s effect and thus reduce her chance of developing breast cancer.

In conjunction with a team from Pennsylvania State University, Russo’s group executed a trial on mammary tumors in rodents, dividing the rodents into four classes. They fed the groups one of two diets for eight weeks: either a 17% fish oil diet, with or without a well-known estrogen inhibitor (tamoxifen) or a 20% corn oil diet, with or without the drug. Then, gene expression patterns in the tumors were analyzed. The data collected suggest that the mix of fish oil and estrogen inhibitor reduced the expression of genes associated with tumor growth and spreading. In addition, the fish oil was said to increase the expression of genes that activate immune defenses more than the corn oil. But, it also increased other immune responses such as inflammation and allergic reactions, which could lessen healthy cells’ ability to attack cancer cells and may cause tumor cells to migrate.

Stated Russo, “If a tumor was being treated with the drug, the addition of an omega-3 fatty acid diet seemed to make the tumor, at least at the molecular level, more benign and less aggressive and responsive to the drug.” But, advises Russo, “More studies are needed to fully understand the effects of fish oil on the immune system.” Study findings were presented on April 6, at the American Association for Cancer Research (AACR) 102nd Annual Meeting 2011.